spring Bean的三种配置方式

时间：2021-05-18 20:47:28

Spring Bean有三种配置方式：

  • 传统的XML配置方式
  • 基于注解的配置
  • 基于类的Java Config

添加spring的maven repository

<dependency>

      <groupId>org.springframework</groupId>

      <artifactId>spring-core</artifactId>

      <!--这个jar文件包含Spring框架基本的核心工具类，Spring其它组件要都要使用到这个包里的类，是其它组件的基本核心 -->

      <version>4.1..RELEASE</version>

    </dependency>

    <dependency>

      <groupId>org.springframework</groupId>

      <artifactId>spring-context</artifactId>

      <!--这个jar文件为Spring核心提供了大量扩展 -->

      <version>4.1..RELEASE</version>

    </dependency>

    <dependency>

      <groupId>org.springframework</groupId>

      <artifactId>spring-test</artifactId>

      <!--对JUNIT等测试框架的简单封装 -->

      <version>4.1..RELEASE</version>

    </dependency>

    <dependency>

      <groupId>org.springframework</groupId>

      <artifactId>spring-tx</artifactId>

      <!--为JDBC、Hibernate、JDO、JPA等提供的一致的声明式和编程式事务管理。-->

      <version>4.1..RELEASE</version>

    </dependency>

    <dependency>

      <groupId>org.springframework</groupId>

      <artifactId>spring-beans</artifactId>

      <!--这个jar文件是所有应用都要用到的，它包含访问配置文件、创建和管理bean以及进行（IoC/DI）操作相关的所有类 -->

      <version>4.1..RELEASE</version>

    </dependency>

    <dependency>

      <groupId>org.springframework</groupId>

      <artifactId>spring-jdbc</artifactId>

      <!--这个jar文件包含对Spring对JDBC数据访问进行封装的所有类。 -->

      <version>4.1..RELEASE</version>

    </dependency>

    <dependency>

      <groupId>junit</groupId>

      <artifactId>junit</artifactId>

      <version>4.12</version>

    </dependency>

一、传统的XML配置方式

　　BeanFactory.java

package com.stonegeek.service;

/**

 * Created by StoneGeek on 2018/5/13.

 */

public interface BeanFactory {

    public void Beantest();

}

　　BeanFactoryImpl.java

package com.stonegeek.service.impl;

import com.stonegeek.service.BeanFactory;

/**

 * Created by StoneGeek on 2018/5/13.

 */

public class BeanFactroyImpl implements BeanFactory {

    @Override

    public void Beantest() {

        System.out.println("----------------This is a 传统的XML配置的bean!-------------------");

    }

}

　　applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>

<beans

        xmlns="http://www.springframework.org/schema/beans"

        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

        xmlns:context="http://www.springframework.org/schema/context"

        xsi:schemaLocation="http://www.springframework.org/schema/beans

    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd

    http://www.springframework.org/schema/context

    http://www.springframework.org/schema/context/spring-context-3.0.xsd

    ">

    <bean id="beanFactroy" class="com.stonegeek.service.impl.BeanFactroyImpl" />

</beans>

　　TestBean1.java

package com.stonegeek;

import com.stonegeek.service.BeanFactory;

import org.junit.Test;

import org.springframework.context.ApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;

/**

 * Created by StoneGeek on 2018/5/13.

 */

public class TestBean1 {

    @Test

    public void test(){

        ApplicationContext ctx= new ClassPathXmlApplicationContext("applicationContext.xml");

        BeanFactory beanFactory=(BeanFactory) ctx.getBean("beanFactroy");

        beanFactory.Beantest(); //----------------This is a 传统的XML配置的bean!-------------------

    }

}

二、基于java注解的配置

　　如果一个类使用了@Service，那么此类将自动注册成一个bean，不需要再在applicationContext.xml文件定义bean了，类似的还包括@Component、@Repository、@Controller。

　　然后需要在applicationContext.xml文件中加一行，作用是自动扫描base-package包下的注解：

<context:component-scan base-package="com.stonegeek" />

　　BeanFactoryImpl.java

package com.stonegeek.service.impl;

import com.stonegeek.service.BeanFactory;

import org.springframework.stereotype.Service;

/**

 * Created by StoneGeek on 2018/5/13.

 */

@Service("beanFactory")

public class BeanFactroyImpl implements BeanFactory {

    @Override

    public void Beantest() {

        System.out.println("----------------This is a 基于Java注解的bean!-------------------");

    }

}

　　applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>

<beans

        xmlns="http://www.springframework.org/schema/beans"

        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

        xmlns:context="http://www.springframework.org/schema/context"

        xsi:schemaLocation="http://www.springframework.org/schema/beans

    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd

    http://www.springframework.org/schema/context

    http://www.springframework.org/schema/context/spring-context-3.0.xsd

    ">

    <context:component-scan base-package="com.stonegeek" />

</beans>

　　TestBean2.java

package com.stonegeek;

import com.stonegeek.service.BeanFactory;

import org.junit.Test;

import org.springframework.context.ApplicationContext;

import org.springframework.context.support.ClassPathXmlApplicationContext;

/**

 * Created by StoneGeek on 2018/5/13.

 */

public class TestBean2 {

    @Test

    public void test(){

        ApplicationContext ctx= new ClassPathXmlApplicationContext("applicationContext.xml");

        BeanFactory beanFactory=(BeanFactory) ctx.getBean("beanFactory");

        beanFactory.Beantest();  //This is a 基于java注解的bean！

    }

}

三、基于类的Java Config

　　通过java类定义spring配置元数据，且直接消除xml配置文件

　　Spring3.0基于java的配置直接支持下面的注解：

　　@Configuration

　　@Bean

　　@DependsOn

　　@Primary

　　@Lazy

　　@Import

　　@ImportResource

　　@Value

　　BeanFactoryImpl.java

package com.stonegeek.service.impl;

import com.stonegeek.service.BeanFactory;

/**

 * Created by StoneGeek on 2018/5/13.

 */

public class BeanFactoryImpl implements BeanFactory {

    @Override

    public void Beantest() {

        System.out.println("----------------This is a 基于类的Java Config的bean!-------------------");

    }

}

　　BeanConfig.java

package com.stonegeek.service.config;

import com.stonegeek.service.BeanFactory;

import com.stonegeek.service.impl.BeanFactoryImpl;

import org.springframework.context.annotation.Bean;

import org.springframework.context.annotation.Configuration;

/**

 * Created by StoneGeek on 2018/5/13.

 */

@Configuration

public class BeanConfig {

    @Bean

    public BeanFactory beanFactory(){

        return new BeanFactoryImpl();

    }

}

　　TestBean3.java

package com.stonegeek;

import com.stonegeek.service.BeanFactory;

import com.stonegeek.service.config.BeanConfig;

import org.junit.Test;

import org.springframework.context.ApplicationContext;

import org.springframework.context.annotation.AnnotationConfigApplicationContext;

/**

 * Created by StoneGeek on 2018/5/13.

 */

public class TestBean3 {

    @Test

    public void test(){

        ApplicationContext applicationContext=new AnnotationConfigApplicationContext(BeanConfig.class);

        BeanFactory beanFactorys=applicationContext.getBean(BeanFactory.class);

        beanFactorys.Beantest();  //This is a 基于类的Java Config Bean！

    }

}

　　以上就是spring bean的三种配置方式的简单介绍！！

　　

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